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227 Uppsatser om Scots pine. - Sida 9 av 16

Förekomst & kostnad av kapsprickor i stormaskadad skog

The aim for this study where to investigate the frequency of cutting cracks in saw timber harvested in the storm-damaged forests in regions where the storms Hilde and Ivar hit. The idea for this work came from one of the region?s biggest actors, SCA Skog and Jämtlands district. The purpose where to find out how big proportion of the saw timber that contains cutting cracks, their financial cost in lost wood value and also give advice and suggestions on how to work against the frequency of cutting cracks. For the field-study some guidelines where used to make sure that the samples were taken under the same conditions, they were: ? The field-study must be performed under harvesting of storm-felled forest, which are horizontal/inclined trunks. ? The averaged sized tree will make it possible to harvest saw timber. ? The trunks can?t be root cut. A methodology called in Swedish ?Trissmetoden? was used because it is the most frequent used methodology in earlier performed studies and the only one that can be used I field. Under the field-study data were collected from 570 saw timber logs, 30 logs from each one of the tested harvesters.

Rhododendron ur undersläktet Vireya - något om dess karakteristika och användning i nordiska vinterträdgårdar :

Present essay aims to introduce the reader to central topics regarding Rhododendrons of subgenus Vireya. As a result of a donation, the Swedish University of Agricultural Sciences, received a collection of Vireya from a local amateur grower, Kurt Myllenberg. Since the subgenus Vireya is uncommon in Scandinavian horticulture, the study tries to establish conditions for successful growing. The subgenus Vireya differ from the other Rhododendron species through mainly three characteristics: the presence of two tails, attached to each end of the seed; the ovary-style junction is tapering and the pedicels arises directly from a dome-like base and form an umbel and not a raceme. The subgenus is distributed mostly in the islands of Indonesia and New Guinea, but also from Malaysia to Nepal and in Australia. Since Vireya species mainly grows as epiphytes in the tree canopies, they need high drainage and not too much water.

Inverkan av nederbörd, temperatur och frost på årsringens egenskaper hos boreal tall (Pinus sylvestris L.) :

The wide distribution range of our boreal pine (Pinus sylvestris L.) provides a great variation in growing conditions and climate/weather factors that influence the wood development of the trees. A great number of extensive studies have been conducted over the years in order to clarify growth trends of this and other species over more or less wide-ranging areas. In this thesis effects of weather factors were instead compared between different forest stands from the about same geographical location. The effects of precipitation, temperature and frost on the year ring characteristics of pine were studied in the research forest of Svartberget Vindeln, in northern Sweden. The stands differed in site index and silvicultural treatment; fertile ? high stem density, fertile ? low stem density, poor ? high stem density and poor ? low stem density.

Föryngringsresultat och beräknad virkesproduktion i naturligt föryngrade tallbestånd i Västerbotten under mitten av 1990-talet :

According to the Board of Forestry, in Västerbotten, many natural regenerations of Scots pine (Pinus sylvestris) carried out on privately owned forest in the middle of 1990 in Västerbotten have rendered a bad regeneration outcome and will provide a low future forest production. The Board of Forestry believes that the negative result can be explained by the fact that the regeneration has been carried out in wrong locations and that scarification failed to work as planned. In order for an accepted rate of regeneration the guidelines of the Forrest Act require, not less than 10 years after final cutting at natural regeneration, that there should be at least 1300 (site indices 16 m) - 1700 (site indices 20 m) main crop stems per hectare. Main crop stems are defined as stems according to the place of growth and appropriate tree type, in addition with regard to quality, stage of development and damage risk have a prospect of succeeding. In addition main crop stems should be separated by surface so that the proportion sample plots with 3 meters radius, and lack main crop stems, are not more than 10 % of site indices 14 meters or higher.

Kan risken för spontan contortaföryngring elimineras genom hyggesbränning? :

Sweden has almost 600 000 hectares planted with lodgepole pine, and large areas are soon ready to be clear-felled. The provenances that have been planted are producing high level of permanently closed, so called serotinous, cones. In their natural setting, the Canadian boreal forest, these cones are opened mainly after crown fires when the heat make the resin between the cone scales melt, which releases the seeds. This is viewed as an adaption to the fire regimes that prevail over the natural distribution area of lodgepole pine. Because of the short flame-exposure that occurs in a crown fire, the seeds can survive.

Naturliga filtermaterial för reduktion av metaller i dagvatten

Förorenat dagvatten från Stena Gotthards metallåtervinningsanläggning i Eskilstuna har filtrerats genom kolonner innehållande två olika adsorbenter, torv och furubarksflis. Torv är en organisk jordart som främst används som bränsle och furubarksflis är en biprodukt från skogsindustrin. Båda filtermaterialen är relativt billiga och finns i stora kvantiteter i Sverige. Filtermaterialen har visat sig ha varierande kapacitet att adsorbera metaller i vatten på grund av själva materialet samt vattnets sammansättning. Resultatet från den här studien visar att av de två undersökta filtermaterialen så har furubarksflis störst kapacitet att reducera bly, koppar och zink från det specifika dag vattnet..

Hållfasthetssortering av plankor med hjälp av röntgendata

The aim of this thesis is to find a statistical model that sort logs according to a predicted modulus of elasticity on the sawn boards. The input parameters for the model are X-ray variables from an X-ray scanner. For some of the log classes sawn at the sawmill it is desirable to have a narrow distribution of modulus of elasticity on the sawn boards. 250 pine logs from five different diameter classes were numbered and followed through the sawmill process. Log data were collected from X-ray and 3-D scanners in the log intake.

Bungenäsmöbeln : ett examensarbete för Skälsö Arkitekter

The essay describes the bachelor project by Marie Hanås, in collaboration with Skälsö Arkitekter. Skälsö Arkitekter are currently developing an area in the north of Gotland, Bungenäs; previously home to lime stone quarries and military bases.The brief was to design a set of outdoor furniture to complement the new development. The main effort of the project was in designing furniture that would fit the environment visually but construction issues were a major secondary concern, to ensure the easiest possible manufacturing. A reference group of coastal house owners were interviewed, and their feedback, together with an analysis of functions, trends and target groups, were the base for the ideas.Of the five concepts presented, Skälsö Arkitekter chose one to develop further. This was done through sketches, models and 3D models and led to the final result which is lightweight furniture of Gotlandic pine wood with an industrial touch.

AUSTERS 1:61 - ett fritidshus på Gotland

A few hundred metres from the beach on Fårö, Gotland, is a small lot with pine trees, green moss and wild fl owers situated, owned by my brother and sister. Eventually they would like tobuild a summerhouse here, in close proximity to their relatives. My project is a proposal for the summerhouse at the site, within the restrictions of 61 m² building area, with focus on interior,exterior and the environment.My proposal is a house close to the surrounding nature, with reference to the the building tratition on the island and with local materials. Orientation to the sun, road and neighbours hasall infl uenced my ideas of this house and the relation between inside and outdoor living, were important in my creative work. The aim was to create a house made for the family and theirholiday lifestyle and allowed consideration for the possibility of a growing family with more children.

Älgbetesinventering på Orsblecks viltvårdsområde

The purpose with this report is to compare moose browsing in young stands within a small game preservation, and if there are any differences between two areas. The method used in the inventory is a local damage caused by moose browsing survey. It is suitable on areas that have more than 50 hectares but less than 250 hectares of young forest. Inventory of moose browsing is best done on bare ground in the spring and should preferably be done before the flushing begins at the pine. Orsblecks game management area is divided into two different moose management areas, Noppikoski and Siljansringen. During the winter Siljansringen has a denser winter strain of moose, because of the moose seek out lower parts with less snow during the winter. This should also lead to the southernmost part should accommodate larger proportion of damages caused by browsing by moose.

Planering för friluftsliv, biologisk mångfald och skogsbruk i skogsmiljö

Vallentuna municipality in Stockholm County, is planning to develop a management plan for a forest area owned by the municipality. The property is an urban forest and the hiking trail Roslagsleden runs through it. Hence the municipality intends to take extra care of the outdoor recreation interests, as well as forest biodiversity, but at the same time use the area for forestry. This study discusses how these three interests, recreation, biodiversity and forestry, differ in their views of how a forest should be managed, where they disagree and how they can coexist in the management of this area. In this study, a vegetation mapping of the area and an assessment of the forest?s conservation values was carried out.

Betesskador på lärkplantor

The purpose of this study was to show how the Hybrid Larch (Larix eurolepis x) are used by large herbivores in terms of grazing and fraying. More specifically I studied how impact on the seedlings was affected by forest stand area, tree height and stem density (stems/ha).The survey was done in Jönköpings county in southern Sweden. About 50 % of all stems that are measured are damaged by grazing and 5,8 % was damaged from fraying. The conclusion of the study is that the biggest influencing factor is the height of the seedlings. The size of the stands and number off seedlings per hectare have almost no impact on the injuries on the seedlings. Fraying are common on trees smaller than 3 meters, and doesn?t occur on trees above that height.

Stamräkning och identifiering av åtgärdsbehov i röjnings- och gallringbestånd med hjälp av låghöjdsbilder

This report is an assessment of the feasibility of using aerial photographs to estimate number of stems per hectare in young forest stands, used together with upper height to determine the need for pre-commercial thinning or ordinary thinning cutting. Aerial photo-interpretation was conducted in 2007 on assignment of Stora Enso Skog AB. A mean height function based on stand age produced with data from Bergvik Skog AB?s 2006 forest inventory assessment was used as a proxy for upper height and used together with photo-interpreted number of stems per hectare to determine the need for thinning cutting according to Bergvik Skog AB?s definitions. The test area is located north of Falun on Bergvik Skog AB?s land.Flight altitude was approximately 900 m above ground and the aerial photos were taken by L&L Flygbildteknik AB.

Effekter av gödsling i äldre tallbestånd på renbetesväxter i fält- och bottenskikt :

Reindeer husbandry and Forestry are both area related industries and will in big extent use the same lands. Conflicts often arise because of that the industries have different interests. Many of the activities done by the forestry influences the reindeer husbandry in an undesirable way, simultaneously as the reindeer husbandry activities can have negative consequences for the forestry. One such forestry activity is fertilization. It was during the 1960´s forest fertilization began to be practiced and the reason was that the increase in growth that the fertilization gave could be able to cover for the future shortage in wood many feared. During the 1970´s when the fertilizing activities were most intensive about 200 000 ha was fertilized annually.

Människans roll i skogslandskapets trädslagssammansättning, en studie i Ångermanland

Human presence has always influenced the surrounding areas, the forest as well. Structure and species composition have changed during human land use. Knowledge regarding these changes should be of great interest for conservation and forestry. We have analyzed human impact on the tree species composition on five study sites during 2000 years in Ångermanland, Sweden. More specifically the change in tree species composition in percentage amongst alder, birch, spruce and pine over time.

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